Script to install 2008 Client Side Extensions, XP Only

Below is the script that I found and going to start testing. I only want it to be installed on XP machines. Any suggestions on how I can specify this?

--START--

sExePath = "\\mydomain\netlogon\Login Scripts\Global\winxp-cse.exe"
sSwitches = "/quiet /passive /norestart"
Set oShell = CreateObject("WScript.Shell")
sRegKey = "HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate"
' suppress error in case values does not exist
On Error Resume Next
' check for marker
sRegMarkerValue = ""  ' init value
sRegMarkerValue = oShell.RegRead( sRegKey & "\CSEInstalled")
On Error Goto 0
' to be sure update is installed only once, test on marker
If sRegMarkerValue <> "yes" Then
   oShell.Run Chr(34) & sExePath & Chr(34) & " " & sSwitches, 1, True
   ' create marker
   oShell.RegWrite sRegKey & "\CSEInstalled", "yes"
End If
 
--END--